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Sunday, February 6, 2011

The Latest on the New Coastal Radar

A number of you have asked about the status of the new coastal weather radar--the one destined for the Washington Coast. At the recent annual meeting of the American Meteorological Society, several of us had the chance to sit down with the NWS folks that are responsible for the installation of the new radar. Let me tell you what we have learned.

Bottom line: the National Weather Service is confident that the new radar will be operational by the end of September (2011).

So by the start of the next storm season, we will finally be able to see the details of incoming storms and weather systems. This is fortunate--next year will probably be a neutral El Nino Southern Oscillation (ENSO) year...neither El Nino nor La Nina. Such years are the ones when the most powerful storms hit our region (but no guarantees storm lovers!!)

Now the details.

First, the location of the radar is now public knowledge: Langley Hill in Grays Harbor County (see map). A wonderful location, with clear views out to the Pacific Ocean (see coverage map below for .5 degree elevation angle). And the radar will able to see the heavy precipitation on the windward side of the Olympics and over the Willapa Hills. The National Weather Service is close to signing the final paperwork for leasing that site.Second, the National Weather Service now has our radar in hand. This is not a new radar, but one used for training purposes by the military (and the only one available) and identical to the radars used by the NWS over the rest of the country (known as the NEXRAD or WSR-88D radars). I was told it was "lightly used" , sort of like buying a used car from an elderly grandmother. It will be completely refurbished and updated before installation. Using a preexisting radar not only saves money, but the NWS folks know how to maintain and service it. They were nervous about getting a new radar--one different than the current network.

Third, our radar will be one of the first in the nation to be updated with dual-polarization. All the current radars are single polarization, which means the electromagnetic radiation it emits has only one orientation--horizontal (see figure). In dual polarization, two orientations (horizontal and vertical) are emitted and received. Why is this good? Well, by getting the two orientations all kinds of magic is possible---determining the shape and type of precipitation, getting a much better handle on the intensity of precipitation (especially in terrain), and more. Eventually all the NWS radars will have it, but this will be one of the first.

Fourth, our radar will be the ONLY one in the nation using a zero degree scan angle. Weather radars scan in two ways. First, they constantly turn in azimuth (0 to 360 degrees). During the first scan the antenna is directly at an angle .5 degree above the horizon. Then it does a scan at 1.0 degrees, then 1.5 degrees, etc. Here is a figure that shows you the height of the radar beams for the various scan angles close to the radar (up to 120 nautical miles, 220 km).Now the lowest scan is near the surface close to the radar, but get 100 km out and the beam is 1000 meters up in the air! And at 200 km out the beam is 2000 meters (over 6000 ft) above the surface. So you are missing what is happening lower down. These radars can view 300-400 km out, so you can miss a lot at low levels, particularly at a distance. And WE want to see as much as possible at low levels over the Pacific!

Several of us have pushed the NWS to do something special with this radar, allowing a zero degree angle, and they have agreed. This will allow us to see much farther out at low levels than normal and will be a boon for viewing weather out over the Pacific. Again, no other NWS radar in the country has this capability--hopefully our radar will inspire the NWS to try this elsewhere.

During the next few months, a lot of action will begin at the site. Trenching for utilities, putting down a concrete pad, erecting a building for the generator, putting up the tower, and more. The radar should be installed midsummer. By late September a local meteorological revolution will occur and for the first time one of the stormiest areas in the country will be able to see incoming storms. And folks in the coastal communities and those in the marine industries of the Washington Pacific coast will have what the rest of us have enjoyed for years...decent weather radar coverage, with all the safety and economic benefits. Finally, I should note that Senator Maria Cantwell deserves credit for getting the resources to make this happen.

With good radar coverage, incidents like the New Carissa grounding (on the Oregon Coast), will hopefully be less frequent.

23 comments:

Cliff said: "Fourth, our radar will be the ONLY one in the nation using a zero degree scan angle."

I suspect that might break a few websites out there that have "advanced" WX options (that give scan angle options) unless they're smart about adding a fix to both the UI for this one radar.

That said it's an ideal place to look out "flat" with most of that coverage over the sea (and I presume not too much local ground clutter?).

Has that been tested (not operational) at another sites?

Finally I noticed that that radar coverage map for Langley Hill is different from the one in one of your earlier presentations (a seaward wedge is no longer 50% coverage). Is it on a higher tower? Or is this an updated calculation?

See page 29 in this PDF of Cliff's PPT presentation to the PNW Weather Workshop last year is here:

Lets hope that we have better, more accurate ski forecasts, given the disaster of the last month: One minute...big storm coming in! Next minute: rain at 6,500 feet! What a frustrating month for skiers! If it's not Ridgezilla, it's Rainzilla. I have no doubt we'll have great snow in March (we ALWAYS do) but I was hoping we wouldn't have a winter doldrum like this. The radar won't fix it, but hopefully we won't get our hopes up as often, only to have them dashed! Everyone can deal with a lack of new snow, it's the tease that hurts!

I was hoping that next year would be a "nuetral" year....but Joe Bastardi from Accuweather said that La Nina may continue into next fall/winter as well. He also said the next 3 out of 5 winters could be as bad or worse than this winter was. For us...well...that wouldn't be all that bad since this year (so far) hasn't been as "extreme" as they first forcast it to be. Yes....I am a big storm lover! Just wondering what our summer will be like this year too....the weather seems like it's just gone wacko everywhere! I'm still not letting my guard down....sooner or later we're going to get hit with something crazy! But I'll stick with your forcasts, Cliff! Joe seems to do good for the midwest/east/etc....but you're the best for the northwest!

You deserve a lot of credit for this too, Cliff. I know you'll never say so yourself, but your consistent efforts at getting this done are a major reason why we'll be able to enjoy the benefits of this next year. Can't wait!

I often travel to the coast for wind and/or waves... currently I base my weekend go/no-go decision based on NOAA's 9pm or 3am Marine forecast update on Friday Night/early Saturday morning.

Cliff, with this new coastal radar, how do you feel Marine forecasting will be affected? With respect to the accuracy of Marine forecasts, which forecast time period, t-6hr, t-12hr, t-24hr, t-48hr..., do you see improving the most?

I have been using your blog to keep an eye on emerging weather patterns. I always have a problem in the spring time with my allergies. I spoke with an allergist in Dallas and he said levels of allergens can be different from year to year is this true?

Do you expect sea return/ground clutter issues with the zero degree angle?

Absolutely, that's why the NWS has not announced this feature but only that it is being tested at the new site. The Dr.is spreading information that is not agreed to or proven scientifically. It's a good thing to investigate but not promise miracles until it is tested and proven. I'll be following this and hope you do too. There are several mountain top NEXRADs that need lower than 0.5 degree scanning where there will be no clutter problems. Congratulations on your new NEXRAD!

DCOckie is not correct. In fact, we did have a radar with zero degree angle in place in 2001 for the IMPROVE field program. The clutter issues were minimal and I would expect the same for this radar which is located at an ideal site for it.

Langley hill is currently populated by seasonal and year round residents. Our homes are situated below the proposed site and within approx 1000 ft. of it. We wonder if the vertical component of this system will have any health effects.

Clair There are no health issues. First, the beam will be aloft, so there is no issue. Second, it weakens very rapidly with distance. Third, these are microwaves, not ionizing radiation like x-rays. On Camano Island there are residents on the next property and there is not even any height difference. Anyway, there should be zero impact on your from this unit other than improving your weather information...cliff